Apparatus for forming serpentine hollow bodies.



PATENTED MAY l2, 1903'.A

- LPARK. APPARATUS 'FOR FORMING SERPENTINB HOLLOW BODIE.

APPLICATION FILED APB.. 1'7, 1902.

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PATBNTBD MAY 12. 1.903;

, No.l 727,830.

A K.PARK. APPARATUS POR P ORMING SBRPENTINE HOLLOW BODIES.

APPLICATION FILED APB. 17, 1902.

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A|y/////////////fl iN-miss STATES Fatented May 12, 1903. PATENT Orrrcs.

KENNEDY PARK, OF CAMBRIDGEPORT, MASSACHUSETTS.

APPARATUS FOR` FORMING SERPENTINE HOLLOW BODIES.

SPECIFICATION forming' part of Letters `Patent No. 727,830, dated May 12, 1903.

' y Application inea April 17, 1902.

To @ZZ nifl/0m it may concern:

Beit known 'that I, KENNEDY PARIQof Oambridgeport, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Apparatus for Forming Serpentine Hollow Bodies, of which the following is a specification.

This invention relates to the manufacture of serpentine headers which are rectangular in cross-section and iiat on two opposite sides, the other two sides being serpentine. Headers of this* character are used in sectional steam-boilers wherein the serpentine sides are nested together.

Serpentine headers are commonly made by applying pressure to a length of wrought-iron pipe or tubing in such manner as to change the form of its cross-section and impart to it The Hat and serpentine sides above referred to, the process being applied by two pairs of dies, the members of one pair beinglat and the members of the other-pair corrugated. Heretofore the tube has been internally supported against the pressure of the diesby a mandrel formed to impart the desired shape to the interior of the header. It is 'impossible, however, to remove the mandrel bodily from the formed header, it being customary to make the mandrel in separable sections, so that the mandrel can be dissected and removed piecemeal fromV the header after the forming operation. The construction of a sectional mandrel is expensive and much time is required in separating and reassembling its parts.

My invention has for its object, first, to dispense with a sectional mandrel or other rigid internal support and to provide instead a yielding internal support adapted to conform accurately to the external dies and to be readily inserted in and removed from the header.

The invention valso has for its object to provide certain improvements in the form and construction of the dies and in the means for operating the same.

The inventionv consists in the improvements which I will now proceed to describe and claim. i

Of theaccompanying drawings, forming a part of this specification, Figure 1 represents a top plan view of an apparatus embodying :tion on the line 2 2 of Fig. 1. Asents a sectional Viewl of a portion of the ap- 'a section on the line 4.4 of Fig. 1. represents a sectional view of the portion of sain No. 103,361. or@ model.)

my invention, the parts of the apparatus being shown in section. Fig. 2 represents a sec- Fig. 3 repreparatus on a larger scale. Fig. 4i represents Fig. 5

one of the serpentine dies, showing the same with the crest of its waves diagonally ar-` ranged. Fig. 6 represents a face View of the portion of the die shown in Fig. 5. Fig. 7 represents in separate views the tubel from which the'hollow bodyis formed. Fig. 8 represents in separate views a` complete serpentine header as formed` by myimproved apparatus, withthe exception of the tube-receiving holes, which are formed in the header by a subsequent operation. Fig. 9 represents in separate views the form of serpentine pieces produced by the serpentine die represented in Figs. 5 and 6. Fig. 10 represents a sectional View of the sliding abutment and of the portion of the movable ram member or follower, hereinafter referred to.

The same characters of reference indicate 'the same' parts inv all the figures.

On the drawings@ a represent die-carriers, which are mounted to rotate or oscillate on Vfixed centers b b, the carriers a a, being preferably circular, as shown in Fig. 1. Each die-carrier has a serpentine die-face c, adapted to act progressively in forming the serpentine sides 2 2 on the serpentine header 5,the said serpentine dies being here shown assegmental and occupying only portions of the peripheries of the die-carriers. At theopposite ends of the serpentine dies arexformed flatdie-faces c c', adapted to form the Iiat portions 4 4 at the endsof the serpentine sides of the header. The blank for theheader is a length of wrought iron or steel tubing 1. (Shown in Fig. 7.) Before the forming operation an end piece 5 is welded rmly in the leading end of the tube 1, and a conformable freely-flowing support d is placed in the tube, such support, as shown in Figs. 1, 2, and 3, being a mass of loose hardened-steel balls of small size, preferably about threeeighths of an inch in diameter, although the diameter of the balls may be varied to suit the size of the fillets or grooves and the serpentine edges of the header. 1 do not limit myself, how- IOO ever, to an internal support composed of balls, as any other suitable internal support which is adapted to be readily poured into and out of the tube and is practically non-compressible, although conformable and eXtensible, so it will aord an adequate internal support for the tube against the pressure of the dies, may be used. It is obvious that a suitable liquid might be employed as the flowing intern-al support, although for various reasons I prefer the form of support first described. The die-carriers are provided With abutmentpieces c2 c2, arranged to meet and form an abutment for the leading end of the tube l when the latter is first presented at the nip of the serpentine dies. The dies are moved in unison on their centers b b by means hereinafter described and in the direction indicated by the arrows in Figs. l and 3, the serpentine dies c being thus caused to act on the tube progressively and form the two serpentine sides 2 2. At the same time the two pairs of side dies c3 c3, formed on the die-carriers at opposite sides of the serpentine dies, cooperate in forming the llat sides 3 of' the header, the acting faces of the said dies c3 c3 being the inner sides of flanges formed on or attached to the die-carriers and projecting outward from the serpentine dies c. It will be seen that as the sides of the tube are indented by the serpentine dies the metal displaced is caused to fit closely against the side dies and is carried rearwardly, elongating the tube.

The conformable internal support CZ is held at its front end by the plug 5 and is yieldingly supported at its rear end by an abutment e, which has a sliding t in the tube 1 and bears against the rear end of the support d. Said abutment is given a forward yielding movement, so that it follows the general end Wise movement of the tube caused by the rotation of the die-carriers and at the same time yields to the extent required by the extension or elongation of the tube and of the support d. I have here shown as the preferred means for applying the described yielding pressure to the abutment e a hydraulic ram, the piston fof which has a rod or follower f', arranged to engage the abutment e and force the same toward the nip of the dies. The cylinder f2 of the ram has suitable inlet and outlet passages f3 f4, a suitable valve mechanism being provided for admitting Water under pressure first into one and then into the opposite end of the cylinder, Water being admitted through the passage f3 during the forming operation and pressing the piston toward the nip of the dies. After the forming operation and when it is desired to Withd rauT the piston or move it from the nip of the dies the Water is admitted through the passage f4 and allowed to escape through the passage f3. The described yielding movement of the abutment e is or may be provided for by means of a pressurevalve g, located in an outlet-pipe g at one end of the ram-cylinder, said valve being set or adjusted to the pressure required to bend or indent the metal of the tube.

The die-carriers ad are moved in unison by suitable means, the extent of movement be- Aing sufcient to cause the serpentine dies to act on the entire length of the tube and deliver the same completed so 4far as the form of its sides 2 2 and 3 3 are concerned at the delivering side of the carriers. I have here shown as the means for operating the die-carriers a hydraulic ram, the piston h of which is connected by its rod 7i with a cross-head i, the latter being connected by rods j 7' with the die-carriers. The cross-head i is adapted to slide on guides t" i on the base 7c, said guides directing the movement of the crosshead. Water under pressure is submitted to and allowed to escape from the ram-cylinder 71.2 to passages h3 h4, a suitable valve mechanism being employed to reverse the direction of the Water and of the movement of the piston 7L. The extent of the movement imparted to the die-carriers is regulated bythe said valve mechanism controlled by an attendant.

The parts above described are mounted upon a suitable supporting-base 7c. The centers b b on Which the die-carriers move are preferably adjustable on said base toward and from each other to compensate for the variations in the thickness of the Walls of the headers. Each center b is here shown as afiixed to a dovetail slide b', (see Fig. 4,) fitted in a dovetail groove in the base k and adj ustably secured to the base by suitable means.

m represents a guide adapted to direct the movement of the tube or blank l toward the nip of the roll of the die, said guide being composed of two parallel upright flanges on the base 7c.

If desired, each carrier Ct may have more than one sepentine die. I have here shown a second serpentine die c4, formed on each die-carrier. The dies c4 may be formed with the crestv of their Waves extending obliquely relative to the axis of the die-carrier instead of parallel to that axis. The dies cAk are thus adapted to form serpentine sides with obliquely-extending waves, as shown in Fig. 9. To make the serpentine dies c4 operative, the rods jj are to be disconnected from the points to which they are shown as connected in Fig. l and engaged with the die-carriers at the points jj'. One or more of the Waves or fillets of each serpentine die may be detachable, as indicated by dotted lines in Fig. 1, to vary the length of the die.

In Fig. l I have shown the serpentine dies as occupying about one-half of the peripheries of the die-carriers, the remaining portion of the peripheries being occupied by segmental die-faces c5 c5, which are formed to cooperate With the sidedies c8 in forming two flat sides or a box-shaped header Which is not serpentine. When the die-faces c5 are to be used,

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the connecting-rods j are engaged with the die-carriers at the pointsj2 o o represent holding-down ilanges, which are affixed to the base 7c, and projecting over the lower flanges c3 of the die-carriers to prevent the carriers from being tipped.

The abutment e is preferably flexible, so that when the form of the portion of the tube immediately surrounding it begins to change, the abutment will conform to the changed shape of the tube. The abutment is preferably madein the form ofahollow cone of sheet metal, its larger end fitting the interior of the tube and changing in shape as the portion of the tube surrounding it changes. The smaller end of the abutment engages a cup formed in the outer end of the rod or follower f.

The operation of the described apparatus is as follows: The die-carriers being adjusted, so that the abutments c2 c2 are somewhat at the left to the point of closest. approach of the roll as the apparatus is viewed in Fig. l, the tube or blank l, with its forward end closed by the plug 5 and with the conformable inner support cl in position, is placed against the abutments c2 in the guide m. The sliding abutment e is placed in position in the tube directly after the introduction of the filling d and serves to retain said filling in place while the parts are being attached. The rod or followerf of the abutment-pressing rainis then engaged with the abutment e. The operator then admits water under pressure simultaneously to the cylinders of the two rams, causing the die-carriers to rotate, thus drawing the tube forward and commencing to form it into a header, the rod or follower f and the abutment e at the same time moving forward at a rate which is determined by the elongation of the tube or blank by the action of the die. The forming or action progresses until the entire blank has `been formed and converted into apartially-complete header, which is ejected by the continuous movement ot` the die-carriers in the direction indicated. After the ejection of the formed headerthe operator reverses the valve mechanism and causes the pistons fand h to move in the opposite direction, thus moving the die-carriers back to their starting position and withdrawing the rod or followerf from the space within the die which is to be occupied by the next blank. In order to secure the best results, the blank should be heated prior to the forming operation to a suitable degree to enable it to be easily worked.

Having thus explained the nature of the invention and described a way of constructing and using the same, although without attempting to set forth all of the forms in which it may be made or all of the modes of its use, I declare that what l claim isl. An apparatus of the character described comprising dies adapted to externally form a serpentine hollow body, a conformable lowing support for the interior of said body, and

a yielding abutment opposing the extension of-said support. l

2. .An apparatus ofthe character described comprising dies adapted to externally form a serpentine hollow body, a conformable liowing support for the interior of said body, an* abutment havingasliding fit in said body and 4. An apparatus of the character described comprising two die-carriers mounted to rotate or oscillate on fixed centers, and provided with progressively-acting serpentine dies ar-v ranged to form serpentine sides on a hollow body, and withprogressively-acting side dies arranged to form saidbody between the serpentine sides, means for moving said carriers in unison, a conformable liowing support for the interior of said body, and means for ad- Vancing said support in the direction of movement ofthe said body. f

5. An apparatus of the character described comprising two rotary or oscillatory circular die-carriers provided with flanges, the inner sides of whichv constitute side die-faces and with peripheral serpentine die-faces between said iianges, means for moving said carriers in unison, a conformable iowing support for the interior of said body, and means for adcomprising two rotaryor oscillatory circular die-carriers provided with side die-faces, peripheral serpentine die-faces between said IOO '105 vancing said support in the direction of move- IIO side faces, and abutments for the leading endV of the body to be formed.

7. An apparatus of the character described comprising two rotaryor oscillatory circular die-carriers provided with sidedie-faces, segmental serpentine die faces between said side faces, and fiat die-faces at theopposit'e ends of the said segmental faces.

8. An apparatus of the character described comprising two rotary oscillatory die-holders having progressively -operating serpentine and side dies, and `carrier-operating meansv comprising a hydraulic ram and connections between the piston of said ram and the carriers. '4

9. Au apparatus of the character described y comprising opposed oscillatory' die-carriers having segmental serpentine dies and side dies at opposite sides of said serpentine dies, means for moving said carriers in unison, a tube or blank'guide at the receiving side of the carriers, a conformable Iiowing internal support for a tube or blank in said guide, a

sliding abutment for the rear end of said support, and means for yieldingly supporting and impelling the abutment.

l0. An apparatus of the characterdescribed comprising opposed oscillatory die-carriers having segmental serpentine dies and side dies at opposite sides of said serpentine dies, a tube-guide at the receiving side of said carriers, a hydraulic ram arranged with its movable member in line with a tube in said guide, so that said member can enter and follow said tube, an abutment held hy the movable ram member at the outer end of a conformable flowing-support in said tube, and another hyd raulic ram having its movable member connected with said carriers to move the same in unison.

l1. An apparatus of the charaoterdescribed comprising opposed oscillatorT die-carriers having.,r segmental serpentine dies and side dies at opposite sides of said serpentine dies, a tube-guide at the receiving side of said carriers, a hydraulic ram arranged with its movable mem berin line with a tube in said guide, so that said member can enter and follow said tube, an abutment held by the movable ram member at the outer end of a conformable flowing support in said tube, another hydraulic ram, connections between the piston of said ram and the carriers, said connections including a cross-head, and fixed guides for said cross-head.

In testimony whereof I have affixed my signature in presence of two Witnesses.

KENNEDY PARK. Witnesses:

C. F. BROWN, E. BATCHELDER. 

